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bone, and organ for suckling; but their teeth have little resemblance; and they have neither nostrils, seet, nor hair; instead of nostrils, possessing a spiracle or blowing-hole on the fore and upper part of the head; and instead of feet, fins; in which, as well as in their habits, manners, and residence in the waters, they have a close resemblance to fishes. These are chiefly inhabitants of the polar seas, and several of the larger species afford materials that are highly valuable as articles of commerce or manufactures. All of them produce a considerable quantity of blubber or the basis of the coarst. animal oils; the common whale sometimes to as large a quantity as 6 or 8,000 lbs. weight: from the horny laminae of whose upper jaw, as well as from that of the balaena Physatus or fin-fish, we obtain also extensive layers of whalebone; while the cachalot supplies us with spermaceti from its head, and with abergris from some of its digestive organs; a substance, however, only to be procured from such organs when the animal is in a state of sickness. The most warlike of the order is the grampus, which will often engage with a cachalot
or common whale of double its size, and continue the contest till it has destroyed it. To this order also belongs the dugong or sea-cow of Sumatra, which has of late excited so much attention among naturalists. It was at one time supposed to be a hippopotamus or river-horse, but Sir Thomas Raffles has of late sufficiently proved it to be a cetaceous mammal. It is usually taken on the Malacca coast by spearing: its length is often from eight to nine feet. Its front extremities are two finny paddles; its only hind extremity is its tail, which is a very powerful instrument. It is never sound on land or in fresh water, but generally in the shallows and inlets of the sea; the breasts of the adult females are of a large size, and especially during the time of suckling. Its food seems to consist entirely of fuci and submarine algae, which it finds and browses upon at the bottom of the shallow inlets of the sea, where it chiefly inhabits. Its flesh resembles that of young beef, and is very delicate and juicy.”
* Phil. Trans. 1820, p. 174 * . . . .” --
themselves from the yoke of their Norman Conquer
Thr most remarkable leaning tower in Great Britain is that of Caerphilly Castle, in Glamorganshire: indeed, in proportion to its height, it is much more inclined from the perpendicular than any other in the world of which we can find an account, for it is between 70 and 80 feet high, and 11 feet out of the perpendicular. It rests only on part of its south side, principally by the strength of its cement, the manner of making which is :*:known to modern masons, except to a partial extent. The singularity of its position is best observed by looking at it from the inside, or from the moat immediately underneath it, from whence the effect of the o falling mass is most extraordinary. The castle, of whic this tower forms a part, was built about A. D. 1221; that which previously stood on the same spot having been rased to the ground by the Welsh, in an attempt to free
ors. It is inserior in extent only to Windsor Castle, and must have been one of the most magnificent in the kingdom, its various outbuildings and fortifications covering nearly eleven acres; it is situated on a small plain, bounded by rising ground of very moderate elevation, about nine miles north of Cardiff. It is still a noble ruin, and the great hall is particularly worthy of notice: The fine form of its Gothic windows, and the clustered flying pillars which project from different sides of the room, and from which spring the vaulted arches of the roof, give an uncommon charm to the justness of its proportions. The cause of the inclination of the tower alluded to is not a little singular. The unfortunate King Edward the Second, and his favourites the Spencers, were here besieged by the forces of the Queen, and many powerful Barons in 1326. The defence was long and bravely conducted, and the besiegers were particularly annoyed by metal in a melted state being thrown down on them, which was heated in surnaces still remaining at the foot of the tower, and during their partial success in a desperate assault, (which ultimately failed.), they let the metal, which was red hot, run out of the surnaces, and, either from ignorance or design, threw water from the moat on it, which caused a violent explosion, tore the tower from its foundations, and hurled it into its present position. The solidity of its wall is amazing, and it has resisted the ravages of time in a remarkable manner, the only rents now visible having been caused by the explosion; the storms of more than five hundred years have scarcely displaced a stone from the summit, and the whole surface is almost without a flaw. The castle at length surrendered, the king, whose tragical end is familiar to all, having previously escaped. The Spencers were beheaded at Bristol, and their castle never regained its ancient splendour. It had long been the dread of the neighboring Welch, to restrain whose frequent risings it was built; a song by one of their Bards is yet preserved, in which he prays that his enemy's “soul may go to Caerphilly;” and “going to Caerphilly,” in a similar sense, was by no means an uncommon phrase in that country.
The present state of these towers is not without its
moral; for, in 1ecalling to our thoughts times happily for us gone by, when the fury of faction and the violence of civil war rent the kingdom to its foundation, disfiguring and distorting what they yet failed to destroy, we may look upon such ruins at once as monuments of the past, and as warnings for the future.—Saturday Mag.
PITCH LAKE OF TRINIDAD.
NEAR Point la Braye, Tar Point, the name assigned to to it on account of its characteristic feature, in the island of Trinidad, is a lake which at the first view appears to be an expanse of still water, but which, on a nearer approach, is found to be an extensive plain of mineral pitch, with frequent crevices and chasms filled with water. On its being visited in the autumnal season, the singularity of the scene was so great, that it required some time for the spectators to recover themselves from their surprise, so as to examine it minutely. The surface of the lake was of an ash colour, and not polished or smooth, so as to be slippery, but of such a consistence as to bear any weight. It was not adhesive, although it received in part the impression of the foot. and could be trodden without any tremulous motion, several head of cattle browsing on it in perfect security. In the summer season, however, the surface is much more yielding, and in a state approaching to fluidity; as is evidenced by pieces of wood and other substances, recently thrown in, having been found enveloped in it. Even large branches of trees, which were a foot above the level, had in some way become enveloped in the bituminous matter. The interstices or chasms are very numerous, ramisying and joining in every direction; and being filled with water in the wet season, present the only obstacle to walking over the surface. These cavities are in general deep in propontion to their width, and many of them unsathomable; the water they contain is uncontaminated by the pitch, and is the abode of a variety of fishes. The arrangement of the chasms is very singular, the sides invariably shelving from the surface, so as nearly to meet at the bottom, and then buging out towards each other with a considerable degree of convexity. Several of them have been known to close up entirely, without leaving any mark or seam.
The pitch lake of Trinidad contains many islets covered with grass and shrubs, which are the haunts of birds of the most exquisite plumage. Its precise extent cannot, any more than its depth, be readily ascertained, the line between it and the neighboring soil not being well defined; but its main body may be estimated at three miles in circumference. It is bounded on the north and west sides by the sea, on the south by a rocky eminence, and on the east by the usual argillaceous soil of the country-Cabinet of Curiosities,
At Manilla, one of the largest of the Philippine islands, palm trees are said to grow in great perfection, and to exhibit no less than forty species. Such is the magnitude of some of them, that a Jesuit missionary having touched there but a few days, had, through the kindness of a friend, a place prepared for him so capacious, that under two palm leaves alone, he was enabled to say mass, and to sleep secure from the most violent rain. The leaves are shaped like a fan with ridges, and so strong, that no rain however weighty can penetrate them.—Ibid.
A lover of natural history cannot lithink be a bad man, as ory study of it tends to promote a calmness and o, of mind, favorable to the reception of grateful and holy thoughts of the great and good He cannot be a cruel man, because he will be unwilling wantonly to destroy even an insect, when he perceives how curiously each is adapted to its station.—Jesse.
We have the pleasure of introducing to our readers two splendid cuts of the moon, in addition to the one given in our last. They are from the English Penny Magazine, and have come to hand just in season to be introduced in their appropriate time and place. The following description of these cuts is from the same work.
The face presented by the moon to us is very nearly the same at all times. Sometimes, however, a little more of the western side is visible, sometimes a little more of the eastern; sometimes, also, there is a little change on the northern edge of the moon, sometimes on the southern. To these little changes, which resemble a slight motion to and fro like that of a penduJum, the name of libration has been given.
Let us suppose, 1stly, that the moon moves round the earth o 2ndly, in the plane of the ecliptic, that
is, that the sun, earth, and moon may be always correct
ly drawn on the paper, it never being necessary to place either of them above or below, and that the paper represents the plane of the earth's orbit called the intic: 3rdly, that the moon itself moves round an axis perpendicular to the plane of the ecliptic in the course of a month; that is, that though the moon moves round an axis, no point which is above the ecliptic ever comes below it, in consequence of this motion. All these sup
positions are near the truth: if they were exactly true, and if the time of rotation of the moon were the same as that of its revolution round the earth, the moon would always present the same face, and there would be no libration. The little variations from these suppositions which actually exist, will serve to explain the latter phenomenon. In the diagram of the next page, E is the position of a spectator on the earth, the diurnal motion of which is neglected for the present. The small circles represent the moon, or rather its equator, one hemisphere of the moon being above, and the other below, the paperThe course of the arrow represents the direction of the orbital motion round the earth. The axis of the moon is a perpendicular to the paper, drawn through the centre of the lunar equator. On the moon's equator, eight spots are marked out, by the figures 1, 2, 3, &c. The left-hand diagram represents the supposition that the moon does not move at all upon its axis, and that on the right hand makes her always present exactly the same so towards the spectator. We shall now proceed to details. --- If the moon does not move at all-upon her axis, and we take the position M, the face-ovesented to the earth, is 32187, 3 being the eastern, and 7 the oro, When we come to *** following *
MAP OF THE MOON.
arrows, since the moon has not moved round at all, the of the spectator, who will in the course of an orbital revospot 3 is still at the top of the figure, but 26 is now the lution, or sidereal month, see all the parts of the moon's boundary of the face presented to the earth, and 7, equator in succession; or at least would see them if the which before was only just visible, has advanced consi- half moon were always visible, or if it were always full derably towards the east, while 8 is in front of the spec- moon. And hence, since the face is always the same, we ator, instead of 1. Every spot comes successively in front | conclude that the moon is not without motion o its axis.
We now come to explain the actual appearance observed, viz. that the moon does always present the same face to the spectator. This is represented in fig. 2, where the spot I is always in front of the spectator, and 37 is always the boundary of the part of the equator presented to view. Hence, when the moon has moved from M to P through an eighth part of a revolution, the line 37 has also made the eighth part of a revolution, and with it the whole moon, round an axis perpendicular to the paper. The revolution is in the same direction as that of the orbital revolution; for while M moves to P, the point 5 moves to the place occupied by 4 in the second position of fig. 1, where there is no revolution round the axis. The same thing is evident from the succeeding positions, whence we have the following proposition; that if the moon moves round the earth uniformly, the continual presentation of the same face to the earth proves that she revolves is upon an axis in the same direction as that in which she moves round the earth, and in the same time. The librations already described prove the errors of the preceding suppositions, and the smallness of the libration proves also the smallness of those errors. The moon does not move uniformly round the earth, but varies her orbital velocity, and also her distance from the earth, the velocity being greatest where the distance is least, and vice versa. Let M be the point at which her distance from the earth is least, or her velocity greatest, and let her move uniformly round her axis in the month as before. She then moves round her axis too slow for the orbital velocity, that is, the lunar day would not be finished in the month if the present rate of orbital motion were kept up. The phenomena arising from this will be in kind (though much smaller in quantity) the same as those exhibited in fig. 1, in which there is no lunar day at all. That is, some of the western edge of the moon will be thrown into view which was not visible before, and this will continue until the slackening of the orbital motion has brought down the latter to the same as that of the moon on its axis. After this, and up to the point opposite to M, where the orbital rotation is least rapid, the motion round the axis is too quick for the orbital velocity, the western edge begins to disappear, and the eastern to be brought forward, and so on. This alternation is called the libration in longitude.— Nextly, the axis of the moon is not exactly perpendicular to the plane of her orbit, being about one degree from the perpendicular. This will produce an effect analogous to that observed in the earth from the sun, which is to us the cause of the change of seasons: during one-half the month, the north pole of the moon will be visible, and the south pole during the other. This change at the north and south disc is called the libration of latitude. Lastly, the spectator is not placed at E, the centre of the earth, but rolls round it by the diurnal motion of the earth. This will, in, he course of the day, discover a little of the eastern and western edges in succession, which is called the diurnal libration. We shall resume the orbital motion in a future paper, and now proceed to say something of the chart of the moon. The first map of our satellite was given by Hevelius, in the year 1645. It was the result of three or four year's observations. He at first intended to designate the different spots by the names of distinguished astronomers; but searing the envy of those whom he might think proper to omit, he preferred using the names of places on the earth. His map accordingly presents various ancient names of places on our globe, disposed according to a fanciful resemblance which he imagined he had found. A large round spot not far from the centre represents Sicily: a chain of smaller spots in the interior of this is Mount Etna, and the island fills up the whole centre of the Mediterranean sea, while the Adriatic is a small bay, about half the size of Sicily, looking towards it, and the Peloponnesus, turning round a cor
ner, divides the lonian Islands from Mount Athos. This .
method of describing the situation of the spots was superseded by that of Grimaldi and Riccioli, who preferred the first idea which occurred to Hevelius, and from them it has decended to us. Riccioli, a strenuous opponent of the doctrine of Copernicus, amused himself by placing that astronomer and his followers in situations indicative of the fate he predicted to their opinions.— Copernicus and Galileo are placed in the part which he called the Sea of Storms, while Kepler is the capital of the Island of Winds.
The plate at the head of this article is reduced from a beautiful engraving of the moon's surface, drawn by Charles Blunt, Esq. and published by Ackermann and Co. Our drawing has been made by Mr. Blunt himself. It represents the full moon in a state of mean libration; that is, the greatest part which ever can be added to the eastern limb by the libration is just equal to the greatest part which, at other times, the western limb receives The lunar equator passes a little above the spots marked 26 and 27; 26 being on the western, and 27 on the eastern side.
The following are the names given to the spots, as numbered on the wood-cut. A number preceded by * denotes a remarkable annular mountain, or elevated ring ; by f it is indicated that there is a mountain in the centre of the ring; $ denotes a remarkable cavity. The letters are attached to the names given by Riccioli to remarkable regions, and relate to ideas which were formed of the state of these regions from their general appearance, for which we need hardly say there is no foundation.
The astronomical phenomena exhibited to the inhabitants of the moon, if such there be, are of a character very different from those of our satellite with regard to us. As nearly the same face is always presented to the earth, it follows, that nearly one half of the moon never sees the earth. Of course, the inhabitants of that hals are too wise to believe travellers who come from the other hemisphere, and tell them of a large variegated ball always suspended over the heads of some, always on the right or left hand of others: and is they have as little mental light on the dark side of the moon as we had in Europe two hundred and fifty years ago, there is a vigorous inquisition armed with power sufficient to catch all believers in the earth, and make them recant. On the light side of the moon, there are of course Magazines, which describe the astronomical appearance seen by spectators on the earth, speculate upon its quick rotation, (nearly thirty days to one of the moon,) and wonder whether the inhabitants are themselves aware of, or incommoded by, the rapid rate at which they turn, and whether they swim in the vapours which surround their root. or live upon them. The earth, when full - to ars to an 1... . as the moon